[advanced-reboot] The destination IP address of the packet chosen by the ansible script match static route of vlan100 sometimes, which will result in the error.

[sean-lang]

Description of PR

Summary:
Fix IP range overlapping. One of dataplane traffic is sent from VLAN interfaces to portchannel ports. The destination IP address of the packet is chosen randomly from the default_ip_range subnet:. The found that destination IP address traffic chosen by the ansible script match static route of vlan100 sometimes, which will result in the error.

test log :
"2020-03-27 17:52:27 : Test params:",
"2020-03-27 17:52:27 : DUT ssh: admin@10.250.0.191",
"2020-03-27 17:52:27 : DUT reboot limit in seconds: 0:00:01",
"2020-03-27 17:52:27 : DUT mac address: 80:a2:35:46:09:99",
"2020-03-27 17:52:27 : From server src addr: 192.168.0.99",
"2020-03-27 17:52:27 : From server src port: 24",
"2020-03-27 17:52:27 : From server dst addr: 192.168.4.40",
"2020-03-27 17:52:27 : From server dst ports: [28, 30, 29, 31]",
"2020-03-27 17:52:27 : From upper layer number of packets: 500",

Dut IP setting :
root@as7816-64x:~# show ip interface
Interface IPv4 address/mask Admin/Oper
--------------- ------------------- ------------
PortChannel0001 10.0.0.56/31 up/up
PortChannel0002 10.0.0.58/31 up/up
PortChannel0003 10.0.0.60/31 up/up
PortChannel0004 10.0.0.62/31 up/up
Vlan1000 192.168.0.1/21 up/up
docker0 240.127.1.1/24 up/down
eth0 10.250.0.196/16 up/up
lo 127.0.0.1/8 up/up
10.1.0.32/32

Type of change

• Bug fix
• Testbed and Framework(new/improvement)
• Test case(new/improvement)

Approach

How did you do it?

Fixed rodan choosen IP issue.
skip subnet of vlan1000.
Modify the algorithm to choose the destination IP from the given route entries in the fib database.
The generate dst_ip flow is shown below.
1.Traverse through all of the route entries in the fib and keep the route entries with the desired next hop in a list
2.Emits an error when the list created in the Step 1 is empty.
3.Choose a route entry randomly from the list created in the Step 1.
4.Choose a ip based on the route entry chosen in the Step 3.

How did you verify/test it?

Ran the warm-reboot, fast-reboot,warm-reboot-sad-vlan-port and warm-reboot-sad-lag-member test on t0/t0-64 topology and it passed. Check the destination IP address of the from server to T1 traffic in test logs not match static route of vlan1000.

Ran the others warm-reboot-sad-xxx and test item on t0/t0-64 topology. Check the destination IP address of the from server to T1 traffic in test logs not match static route of vlan1000.

Any platform specific information?

Supported testbed topology if it's a new test case?

Documentation

[msftclas]

All CLA requirements met.

[lgtm-com]

This pull request introduces 1 alert when merging 78fac16 into 1aa76ea - view on LGTM.com

new alerts:

• 1 for Module is imported more than once

[msosyak]

As I see there is PyTest implementation of reboot tests https://github.com/Azure/sonic-mgmt/blob/master/tests/platform/test_advanced_reboot.py
Should we still run & support the ansible version? Or maybe it is better to switch to PyTest version.

[gord1306]

From my personal perspective, if there is useful logic that can be migrated to the pytest, I think it still worth to patch it.

[yxieca]

@sean-lang can you solve the merge conflict?

[sean-lang]

@sean-lang can you solve the merge conflict?
Fixed it.

[tahmed-dev]

Thanks for you contribution. We are moving away from Ansible version, can you also please update the pytest test case as well.

[tahmed-dev]

can you also please update the pytest version of this test case? Similar template work is done here. The paramter to the ptfrunner is here